Philip Hagan from Tynan, son of Rev Matthew Hagan, is understood to have been discovered by emergency services at his Philadelphia apartment on Saturday after he failed to turn up for work on Friday.
The former Royal School Dungannon pupil had been working in the US for around two years.
Ulster Unionist MEP Jim Nicholson is a member of Aghavilly Parish Church where the Rev Hagan is rector.
Mr Nicholson described the death of Philip Hagan as “tragic”.
Linfield v Portadown Sunday clash: Breakers of the Sabbath will answer to God
NI Weather: 45 pictures of how we enjoyed wall-to-wall sunshine
Thousands expected to take part in 'Derry Day' this weekend
Belfast Pride 2022 organisers ‘may have broken law by seeking to bar transgender critics from parade’
Tom Topping: Heartbroken daughter says ‘world is totally shattered’ after father’s shock death - funeral details released
He said: “The Hagan family are highly respected in the Tynan, Middletown and Aghavilly area of south Armagh and my sympathy goes out to them on the death of young Philip.
“Family bereavement coming up to Christmas is not an easy burden to bear and our prayers and thoughts are with the Hagans at this time.”
Mr Nicholson’s expression of sympathy was endorsed by his son Sam, the deputy mayor of Armagh City, Banbridge and Craigavon Borough Council.
Rev Hagan is the Church of Ireland chaplain to the Northern Ireland Hospice.
Former UUP MLA Danny Kennedy also knows the Hagan family well and said they are “really involved in both the church and the community”.
Mr Kennedy said: “They are well-loved within the area. These are very sad circumstances and this is a very severe blow to the family.”
It is understood a post mortem examination will be held to establish the exact cause of death.